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Let t e r S (contin ued) sign article on sideboards was great (FIVW #138, pp. 42-49), including the text, layout, drawings and photos. The memories of the dark years of Fine Woodworking are almost gone (only a few screaming nightmares on occasion). -Steve Kocsis, Jacksonville, Fla. Altitude might have affected sprayer tests-we were very impressed with your approach to testing and evaluating HVLP (high-volume low-pressure ) units, including our T-55, in "Turbine HVLP Sprayers Keep Getting Better" (FIVW #137, pp. 62-67). However, we wish to convey a few points regarding cfm (cubic feet per minute) ratings. The different ratings are likely due to the way various companies interpret the literature given out by its turbine motor manufacturer. For example, a typical motor used 'in our industry shows a rating of 97 cfm unrestricted. This is for the raw turbine motor, without the adapter fitting installed in the normal outlet (which is nearly 1� in. dia.). We felt a more logical and honest rating was with the hose outlet installed, which has an inside diameter of approximately in. , yielding a rating of 55 � This rating might also be affected by cfm. other variables such as voltage and altitude. After the hose and gun are added, pressure rises in the system, with a corresponding drop in cfm. The difference between tlle air-cap pressure you measured and our stated aircap pressure could be due to altitude. Our testing was done at our Calgary shop (3,700 ft. altitude) with one of the largest needle seats and air caps recommended for use with the T-55. Lower altitude and a standard air cap will yield pressures similar to what you measured. Also your test rig appears to block one of the aircap holes. This would increase the back pressure, making all units (including ours) appear to have better pressure than they actually do. A better way would be to put a T-fitting in the line from the gun body to paint container, negating any impact from your test rig. You mentioned that our unit did not have an air-reduction valve. We do have an air-control valve as an option. It was standard with our T-55 system, but it was removed because it was being used as a shut-off valve during startup and during refilling of the paint container. This practice can cause overheating of the unit and force unnecessary back pressure onto tlle motor of the small two-stage turbine. -Patl'ick Landymore, Lemmer Spray Systems Correction-In "Bench-Chisel Review" ( ness number given for the Harris Tools chisel was incorrect. The correct number is 58e. FIVW 5506, WrItIng an artIcle #139, p. 55), the Rockwell-hard- Fine Woodworking is a reader-written magazine. We welcome proposals, manuscripts, photographs and ideas from our readers, amateur or professional. We'll acknowledge all submissions and return those we can't publish. Send your contributions to Fine Woodworking, P.O. Box Newtown, CT 06470-5506. 12 FI E WOODWORKING